[tz] Summer time during WW2 for Europe/Zagreb

[Miro]

Hi,

I'd like to ask a question regarding Europe/Zagreb timezone for years 1941-1945.
I actually reported a bug in Firefox but that turned out not to be the case.
I'll leave url just in case you need more information:
https://bugzilla.mozilla.org/show_bug.cgi?id=704486

Anyway, I have Arch Linux installed with latest tzdata package: 2011n. Package
information is available at:
http://www.archlinux.org/packages/core/x86_64/tzdata. I noticed weird behaviour
in Firefox when I try to enter some dates during WW2. Basically summer time
doesn't get accounted for. Here is a simple test I ran in Firefox:

8<---------------------------------------------------------
var d = new Date(Date.UTC(1942, 5, 11, 22, 0, 0, 0));

// Firefox 8.0.1, Rhino 1.7 release 3 2011 10 16
d.toString(); // Thu Jun 11 1942 23:00:00 GMT+0100 (CET)

// this is what I expect:
// Chrome15, IE8, nodejs 0.6.2, and code in Java and Ruby
d.toString(); // Fri Jun 12 1942 00:00:00 GMT+0200 (CEST)
--------------------------------------------------------->8

I ran the same test on Arch Linux and on Windows 7. On Windows 7 both Firefox
and Chrome work as expected. Only Firefox under Linux presents date which
doesn't account for summer time. Firefox people told me that Firefox uses native
(from glibc probably) tzdata. Therefore, I expected if I use another software
that uses latest tzdata (assuming 2011n is latest) I'd get the same result. I
used joda-time for that (http://joda-time.sourceforge.net/tz_update.html). But I
got correct date. One that does account for summer time.

I was wondering If you could point me in a correct direction for trying to fix
this bug.

Kind regards